package cn.juforg.util;

import java.security.Key;
import java.security.SecureRandom;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

public class EncryptUtil {
	
	static Key key;
	
	 /**
	  * 根据参数生成KEY
	  * 
	  * @param strKey
	  */
	 public static void getKey(String strKey) {
	  try {
	   KeyGenerator _generator = KeyGenerator.getInstance("DES");
	   _generator.init(new SecureRandom(strKey.getBytes()));
	   key = _generator.generateKey();
	   _generator = null;
	  } catch (Exception e) {
	   e.printStackTrace();
	  }
	 }

	 /**
	  * 加密String明文输入,String密文输出
	  * 
	  * @param strMing
	  * @return
	  */
	 public String getEncString(String strMing) {

	  byte[] byteMi = null;
	  byte[] byteMing = null;
	  String strMi = "";
	  BASE64Encoder base64en = new BASE64Encoder();
	  try {
	   byteMing = strMing.getBytes("UTF8");
	   byteMi = this.getEncCode(byteMing);
	   strMi = base64en.encode(byteMi);
	  } catch (Exception e) {
	   e.printStackTrace();
	  } finally {
	   base64en = null;
	   byteMing = null;
	   byteMi = null;
	  }
	  return strMi;
	 }

	 /**
	  * 解密 以String密文输入,String明文输出
	  * 
	  * @param strMi
	  * @return
	  */
	 public static String getDesString(String strMi) {
	  BASE64Decoder base64De = new BASE64Decoder();
	  byte[] byteMing = null;
	  byte[] byteMi = null;
	  String strMing = "";
	  try {
	   byteMi = base64De.decodeBuffer(strMi);
	   byteMing = getDesCode(byteMi);
	   strMing = new String(byteMing, "UTF8");
	  } catch (Exception e) {
	   e.printStackTrace();
	  } finally {
	   base64De = null;
	   byteMing = null;
	   byteMi = null;
	  }
	  return strMing;
	 }
	 /**
	  * 加密以byte[]明文输入,byte[]密文输出
	  * 
	  * @param byteS
	  * @return
	  */
	 private byte[] getEncCode(byte[] byteS) {
	  byte[] byteFina = null;
	  Cipher cipher;
	  try {
	   cipher = Cipher.getInstance("DES");
	   cipher.init(Cipher.ENCRYPT_MODE, key);
	   byteFina = cipher.doFinal(byteS);
	  } catch (Exception e) {
	   e.printStackTrace();
	  } finally {
	   cipher = null;
	  }
	  return byteFina;
	 }

	 /**
	  * 解密以byte[]密文输入,以byte[]明文输出
	  * 
	  * @param byteD
	  * @return
	  */
	 private static byte[] getDesCode(byte[] byteD) {
	  Cipher cipher;
	  byte[] byteFina = null;
	  try {
	   cipher = Cipher.getInstance("DES");
	   cipher.init(Cipher.DECRYPT_MODE, key);
	   byteFina = cipher.doFinal(byteD);
	  } catch (Exception e) {
	   e.printStackTrace();
	  } finally {
	   cipher = null;
	  }
	  return byteFina;
	 }

	 public static void main(String[] args) {
		  EncryptUtil des = new EncryptUtil();// 实例化一个对像
		  des.getKey("Tg1zP2fjCyM=");// 生成密匙
		  System.out.println("key=ast");
		  String strEnc = des.getEncString("psuso666");// 加密字符串,返回String的密文
		  System.out.println("密文=" + strEnc);
		  String strDes = des.getDesString(strEnc);// 把String 类型的密文解密
		  System.out.println("明文=" + strDes);
		 }


}
